Move optional.h to webrtc/api/

webrtc/common_video/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("../webrtc.gni")
 
@@ skipping 39 matching lines @@
 
   public_configs = [ ":common_video_config" ]
 
   if (!build_with_chromium && is_clang) {
     # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
     suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps = [
     "..:webrtc_common",
+    "../api:optional",
     "../media:rtc_h264_profile_id",
     "../modules:module_api",
     "../rtc_base:rtc_base",
     "../rtc_base:rtc_task_queue",
     "../system_wrappers",
   ]
   public_deps = [
     "../api:video_frame_api",
   ]
 
@@ skipping 58 matching lines @@
     if (is_android) {
       deps += [ "//testing/android/native_test:native_test_support" ]
       shard_timeout = 900
     }
 
     if (is_ios) {
       deps += [ ":common_video_unittests_bundle_data" ]
     }
   }
 }